Control fan speed of Nvidia GPU based on control point

nvidia-fan.py

import sys, time, subprocess

loop_interval = 0.5
control_point_list = ((54, 0), (55, 40), (60, 75), (65, 100))
max_temp_history_length = 20

get_temp_cmd = ["nvidia-settings", "-q=[gpu:0]/GPUCoreTemp", "-t"]
get_control_cmd = ["nvidia-settings", "-q=[gpu:0]/GPUFanControlState", "-t"]
get_fan_cmd = ["nvidia-settings", "-q=[fan:0]/GPUCurrentFanSpeed", "-t"]

set_control_cmd = ["nvidia-settings", "-a", "[gpu:0]/GPUFanControlState=%d"]
set_fan_cmd = ["nvidia-settings", "-a", "[fan:0]/GPUTargetFanSpeed=%d"]

def get_temp():
  result = subprocess.run(get_temp_cmd, stdout = subprocess.PIPE)
  if result.returncode != 0:
    raise RuntimeError("Fuck! I can't get GPU tempature(Return code is %d)!" % result.returncode)
  tempature = result.stdout
  try:
    return int(tempature)
  except ValueError:
    raise RuntimeError("Fuck! I can't get GPU tempature(Invalid stdout)!")

def get_control_mode():
  result = subprocess.run(get_control_cmd, stdout = subprocess.PIPE)
  mode = result.stdout
  if result.returncode != 0:
    raise RuntimeError("Fuck! I can't get GPU fan control mode(Return code is %d)!" % result.returncode)
  try:
    return bool(int(mode))
  except ValueError:
    raise RuntimeError("Fuck! I can't get GPU fan control mode(Invalid stdout)!")

def get_fan_ratio():
  result = subprocess.run(get_fan_cmd, stdout = subprocess.PIPE)
  ratio = result.stdout
  if result.returncode != 0:
    raise RuntimeError("Fuck! I can't get GPU fan speed(Return code is %d)!" % result.returncode)
  try:
    return int(ratio)
  except ValueError:
    raise RuntimeError("Fuck! I can't get GPU fan speed(Invalid stdout)!")

def set_control_mode(sw):
  assert isinstance(sw, bool)
  sw = int(sw)
  cmd = list(set_control_cmd)
  cmd[-1] = cmd[-1] % sw

  result = subprocess.run(cmd, stdout = subprocess.PIPE)
  if result.returncode != 0:
    raise RuntimeError("Fuck! I can't set GPU fan control mode(Return code is %d)!" % result.returncode)

def set_fan_speed(ratio):
  assert isinstance(ratio, int)
  assert 0 <= ratio <= 100
  cmd = list(set_fan_cmd)
  cmd[-1] = cmd[-1] % ratio

  result = subprocess.run(cmd, stdout = subprocess.PIPE)
  if result.returncode != 0:
    raise RuntimeError("Fuck! I can't set GPU fan speed(Return code is %d)!" % result.returncode)

def get_fan_speed_by_tempature(temp):
  if temp <= control_point_list[0][0]:
    return control_point_list[0][1]
  elif temp >= control_point_list[-1][0]:
    return control_point_list[-1][1]
  n = len(control_point_list)
  for i in range(1, n):
    i = n - i
    ct, cs = control_point_list[i]
    if temp == ct:
      return cs
    elif temp > ct:
      nt, ns = control_point_list[i + 1]
      ratio = (temp - ct) / (nt - ct)
      return int(round(cs + (ns - cs) * ratio))

def main():
  assert len(control_point_list) > 0
  pt, ps = -1, -1
  for t, s in control_point_list:
    assert 0 <= t <= 80
    assert 0 <= s <= 100
    assert t > pt
    assert s > ps
    pt, ps = t, s
    del t, s
  del pt, ps

  set_control_mode(True)
  curr_fan_speed = get_fan_ratio()
  temp_history = [get_temp()]
  while True:
    try:
      while len(temp_history) >= max_temp_history_length:
        del temp_history[0]
      temp_history.append(get_temp())
      temp = max(temp_history)
      s = get_fan_speed_by_tempature(temp)
      if s != curr_fan_speed:
        #print(temp_history[-1], temp, s)
        set_fan_speed(s)
        curr_fan_speed = s
      time.sleep(loop_interval)
    except KeyboardInterrupt:
      set_control_mode(False)
      return
    except Exception as e:
      print("Loop Failed: %s" % str(e), file = sys.stderr)
      try:
        set_fan_speed(s)
      except Exception as ee:
        print("Protection failed: %s" % str(ee), file = sys.stderr)

if __name__ == "__main__":
  main()